1. Field of the Disclosure
This disclosure relates generally to apparatus and method for providing high resolution sensor measurements.
2. Background of the Disclosure
Wellbores (also referred to as “boreholes”) are drilled in the earth's subsurface formations for the production of hydrocarbons (oil and gas). A variety of measurements, including pressure and temperature measurements, are made while drilling the wellbore and after the wellbore has been drilled. The measurements made during drilling are generally referred to as measurement-while-drilling while measurements made after drilling are generally referred to as well-logging measurements. A downhole tool, generally referred to as the formation testing tool, is used to withdraw formation fluid samples and to take pressure and temperature measurements while logging the well as well as while obtaining the formation fluid samples. Wireline tools also are utilized for pressure and temperature logging. Quartz pressure and temperature sensors are sometimes used to obtain high resolution measurements. Often a trade-off is made between the data resolution and sampling rate. For example, for certain commercially available quartz pressure sensor to obtain a high resolution, such as 0.001 psi, the gate time is often no less that 1 second. When the sampling rate of eight samples per second (for example) is desired, the resolution drops to about 0.01 psi. In some applications, such as during draw down of the formation fluid samples, current downhole tools often use eight samples per second during draw down and fast-build-up phases and then use one sample per second for stable build-up phases. In such measurements, the quantization error (resolution) effect is larger in the areas with a sampling rate of eight samples per second than in the areas with samples of one per second. High quantization error can reduce the data test confidence as well can cause some difficulties during post-processing of the data.
Therefore, there is a need for improved apparatus and method to provide high resolution downhole measurements, including pressure and temperature measurements.